Free tool
DeveloperUUID Generator
Generate one or many UUID v4 values in your browser for database keys, API idempotency keys, and lab fixtures.
Runs in your browser — your data stays on your device
Free toolUUIDs give distributed systems unique identifiers without a central counter. This free UUID generator creates RFC 4122 version 4 IDs using the browser’s cryptographically strong random source so programming students and API developers can seed REST APIs, demos, and tests without installing software.
How to use the UUID Generator
- 1
Choose how many UUIDs you need (1 to 100).
- 2
Tap Generate UUID v4 to create fresh identifiers.
- 3
Copy individual values into your code, Postman collection, or database seed.
Why UUID v4 dominates modern APIs
Auto-increment IDs leak business volume and collide across shards. Random UUIDs avoid those problems for many web applications. Beginners who generate a few IDs here learn the 8-4-4-4-12 layout before they import a library.
UUID v4 example
A UUID v4 looks like 550e8400-e29b-41d4-a716-446655440000. The third group starts with 4 (version) and the fourth group starts with 8, 9, a, or b (variant). Generate a fresh value above to see a live example.
Guides and next steps
Privacy note
UUIDs are generated locally with Web Crypto. Nothing is sent to our servers.
Frequently asked questions
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